Step 0: As starter use a 1-2-2 ring group.
The weaves Mars, Phobos and Deimos are a family of Sweetpea / Harvest Moon combo weaves, and modifications thereof, that were inspired by weave Mercury. But Mars (and so its descendants) can be seen also as crossover of Soyuz and 4in2 chain - or as Soyuz-modification of Persiantine. This shows, how closely related all these Persian family chain weaves are.
Rings used for the tutorial's samples are BA 1.6mm, coiled on 8mm mandrel, with an AR of 5.35 (finished, closed rings measured). Rings added are marked golden-yellow, and in case of Phobos/Deimos some are marked blue.
Let's begin with basic 'Mars'
Step 0: As starter use a 1-2-2 ring group.
Step 1: Add a single ring, woven backwards, sandwiched between the left ring pair of the weave starter.
Step 2: Add a further single ring, woven forward, sandwiched between the right ring pair of step 0.
Step 3: Add a ring pair, backwards, sandwiching the left single ring that was added in step 1.
Step 4: Add another ring pair, forward, sandwiching the second single ring.
Step 5: Add a further pair, this time as simple 2in2 connection.
Repeat steps 1-5; note that this added segment is rotated 90 degrees against the 1st one. Always use the 1 backwards, 1 forward, 2 backwards, 2 forward, 2 forward succession - added single rings are always sandwiched between previously woven ones, and added ring pairs (except for step 5) sandwiching previous single ones.
Rinse, repeat, always in 1B1F2B2F2F pattern, until wished chain length is reached.
Now let's go on with 'Phobos'
Weave a Mars chain of sufficient length; note that conversion to Phobos (or Deimos) pulls the basic chain a bit tighter, so a bit more as final length is needed.
Step 1: Add two rings on either side, through the single rings (marked yellow here) of the Sweetpea-like cells - the result looks like a 'shaggied' version of Mars.
Step 2: Add two further rings per cell (marked blue here), also on the single-ring side, to build Box-like cells that hold the previously set 'golden' rings - note that you have to weave through three and around two rings in this step. Repeat throughout the chain.
And finally 'Deimos', that is similar but different to Phobos, nevertheless.
Again start with a Mars chain of a bit more than needed length.
Step 1: Add two rings on either side, this time through the paired rings (marked yellow here) of the Sweetpea-like cells - the result looks like another 'Shaggy Mars'.
Step 2: Add two further rings per cell (marked blue here), also on the double-ring side, to build Box-like cells that hold the previously set yellow rings - note that you have to weave through four and around two rings in this step. Repeat throughout the chain.
Have fun weaving the Martian weaves - I hope this will not end in a martyrium... :)
-ZiLi-